This article in The Guardian reports there are 1,652 properties listed as unoccupied in Kensington and Chelsea.
That’s 1652 properties that could be used, not as an investment, but as homes.

(This map shows London’s 20,000 empty homes: Time Out: May 10 2017)
It is estimated there are twenty thousand “ghost” homes across London. That is twenty thousand properties that could be a home to someone.
That is an outrage.
There are many reasons for this, not least because interest rates have been kept at ridiculously low levels since the 2008 crash. Those who have money, have been buying property because it gives them a return. This nugget of information was given to me by the estate agent who sold the flat we rented, when our landlord wanted to sell. Throw into this mix foreign nationals, encouraged by UK based estate agents to buy as an investment, and you have a deepening crisis.
Most people, even those on above average incomes, are priced out of the market.
There are a couple of thing that could be done to stop this kind of hoarding. Interest rates could be increased so those with assets get a decent return on their money. This might force the prices down so hoarding brings less of a return. If interest rates went up, some of those who’ve benefited from historically low interest rates would not be able to afford their mortgage, properties would be repossessed, releasing property into the market, forcing prices down.
This brings with it a whole level of misery I wouldn’t wish on anyone. I also don’t think it would have the desired outcome. I suspect the repossessed properties would be swallowed up by those with pockets deep enough to speculate.
The other strategy is more radicle. The fist half involves extending the rights of private tenants. We need laws that give renters long term leases. Not six or twelve months but five or ten years. People need that kind of stability in their lives. These long term leases also need to come with rent controls. The second half of this strategy is to force the owners of all property that sits empty to become landlords. Your property sits empty for more than six months, you have to rent it out, on a long term lease, at rent controlled prices. Investors will either sell their property because they don’t want to be landlords, or the properties would be used as they were intended, as homes for people to live in.
I can just feel the vitriol coming my way, but the neoliberal market is broken, and we need radicle solutions. These are about as radical a way to home people as I can think. Yes build more affordable homes but also put the stocks we have to better use.